The statements in this section merely provide background information related to the present teachings and may not constitute prior art.
Compressors are utilized to compress refrigerant for refrigeration systems, such as air conditioning, refrigeration, etc. During the compression of the refrigerant within the compressor, a significant quantity of heat can be generated, which may result in the temperature of the discharged refrigerant being relatively high. A reduction in the discharge temperature of the refrigerant can increase the cooling capacity and efficiency of the refrigeration system.
A refrigeration system according to the present teachings may incorporate a liquid-refrigerant injection system that can provide liquid refrigerant to an intermediate-pressure location of the compressor and absorb heat during compression of the refrigerant flowing therethrough. The injected liquid refrigerant may decrease the temperature of the compression process and the temperature of the refrigerant discharged from the compressor.
A refrigeration system according to the present teachings may include vapor refrigerant injection into an intermediate-pressure location of the compressor and may reduce the operational temperature of refrigerant prior to flowing through an evaporator, thereby increasing the cooling capacity. Use of the vapor refrigerant injection in conjunction with the liquid-refrigerant injection system and/or a cooling-liquid injection system may further increase the cooling capacity, efficiency, and/or performance of the compressor.
A refrigeration system according to the present teachings may also include a single-phase cooling-liquid injection system that provides a single-phase cooling liquid to an intermediate-pressure location of the compressor and absorbs heat during the compression of the refrigerant flowing therethrough. The cooling liquid, which may be externally separated from the refrigerant flow, may decrease the temperature of the refrigerant being discharged by the compressor, resulting in an increased cooling capacity and/or an increased efficiency. Use of the cooling-liquid injection system in conjunction with the liquid-refrigerant injection system may further increase cooling capacity and/or increase efficiency of the compressor.
The refrigeration systems according to the present teachings can include a flash tank that separates the vapor refrigerant from the liquid refrigerant. The injected refrigerant vapor and liquid refrigerant can be supplied from the flash tank.
A method according to the present teachings can include compressing a refrigerant to a discharge pressure greater than a suction and discharging the compressed refrigerant from the compressor. A first portion of the discharged refrigerant can be injected into an intermediate pressure location of the compressor, the first portion being predominantly refrigerant vapor. A second portion of the discharged refrigerant can also be injected into an intermediate pressure location of the compressor, the second portion being predominantly liquid refrigerant. Heat generated by the compression can be absorbed with the liquid refrigerant injected into the intermediate-pressure location. The discharged refrigerant can have its pressure reduced and be separated into vapor and liquid portions in a flash tank. The compressing of the refrigerant can include compressing the refrigerant to a discharge pressure greater than a critical pressure of the refrigerant.
Further areas of applicability will become apparent from the description provided herein. It should be understood that the description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the present claims.